Conventional continuously variable transmissions used in vehicles include a belt continuously variable transmission and a toroidal continuously variable transmission. A speed change control device for such a continuously variable transmission determines a target speed ratio or a target input shaft rotation speed in accordance with a vehicle speed VSP and a throttle opening TVO (or an accelerator pedal stroke) (see Japanese Unexamined Patent Application Publication JP8-178063A).
In this case, initialization processing is performed to determine a starting position of a step motor for driving a speed change control valve, and when an ignition switch switches ON, the step motor is driven to the starting position at a predetermined speed, whereupon normal speed change control is performed. Speed change control is begun using as the starting position a position in which a rod of a spool provided in the speed change control valve contacts a stopper, for example.